Technical Field
The invention relates to an electronic device. Particularly, the invention relates to a touch display system, a touch device and a touch display method.
Related Art
In recent years, touch electronic products are well received by consumers due to operation convenience and high intuition thereof, and gradually become a main stream in the market. In the conventional resistive, capacitive and rear projection type touch screens, the capacitive touch screens have the best touch effect, though the capacitive touch screens also have the highest cost, and the cost is increased along with increase of a screen size, which limits the application of the capacitive touch screens.
In order to seek an alternative solution of the capacitive touch screen, an optical touch screen using an optical lens to detect a touch position is developed, which has advantages of low cost and good accuracy, etc., and is competitive in the market, so that the optical touch screen has become another option of the large size touch screen.
For example, an infrared light source can be set at periphery of a liquid crystal display (LCD) panel or a projection screen, and the infrared light source is used to form an optical touch area in front of the LCD panel or the projection screen. Moreover, by capturing a light spot formed on a touch object by reflecting light, a position of the touch object can be determined. Alternatively, by detecting a stylus capable of emitting an infrared light, a position of the stylus can be determined. Although the aforementioned methods can effectively provide a touch function to a large size touch screen, since many infrared lights may stray in an application environment, the known optical touch device cannot distinguish whether the captured infrared light is the infrared light in the environment or the light spot formed on the touch object by reflecting the light, or an infrared light spot emitted by the stylus, so that it is easy to cause a wrong judgement of the touch position. Moreover, in case that a plurality of touch styluses is simultaneously used, the known optical touch device cannot distinguish the infrared light spot compounding to each of the styluses, so that the touch position of each of the styluses cannot be correctly determined.
The information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Further, the information disclosed in the Background section does not mean that one or more problems to be resolved by one or more embodiments of the invention were acknowledged by a person of ordinary skill in the art.